When I run a rsync to backup my home folder over the network like so:

rsync -avhz --progress --delete /home/dbdean/ [email protected]:/home/backups/david/

I seem to have problems with my quite large .VirtualBox/HardDisks/Windows XP.vdi file. Occasionally the wifi will silently fail (the transfer stops, and any other network access is broken). If I reconnect the wifi to my network before the transfer times out, it happily keeps going (and other network access is back), but I can't just leave it unattended most of the time, as I have to keep an eye on it.

I'm guessing this is probably a bug in the wireless card related to a particularly high sustained volume of network usage, but I'm not really sure where to start with diagnosing this problem so that I can provide a good bug report. Or it could be something else, I guess. Any help would be appreciated.

My network card is an Atheros Communications Inc. AR9285, as lspci -k shows:

43:00.0 Network controller: Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express) (rev 01)
    Subsystem: Hewlett-Packard Company Device 3040
    Kernel driver in use: ath9k
    Kernel modules: ath9k